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Biomedical subjects

G Pinto

Publications and source records attributed to G Pinto.

At least 55 records · Page 3Linked to original sources

Progesterone bioconversion by microalgal cultures.

Ten different strains of unicellular microalgae have been used in the bioconversion of progesterone. Regio and stereoselective reduction and hydroxylation of the title compound were induced. A 9,10-seco derivative was obtained in high yield by using Scenedesmus quadricauda.

Biotransformation↗

Fc receptors expression and function in mononuclear phagocytes from AIDS patients: modulation by IFN-gamma.

Fc-receptor (FcR)-mediated phagocytosis and FcR (FcRI, FcRII and FcRIII) membrane expression was studied on freshly separated and cultured monocytes (Mo) from 20 AIDS patients and 20 healthy controls. Both Mo and Mo-derived macrophages from AIDS patients presented a significant defect in their capacity to ingest IgG-coated erythrocytes (EA) compared to control cells. This functional defect did not depend on a decline in the number of FcR+ cells or on a decrease in the expression of FcR on their surface. In fact, the percentages of phagocytes reacting with anti-FcRI MoAb (32.2) or anti-FcRII MoAb (IV.3) were similar for controls and AIDS patients, while the percentage of FcRIII-positive Mo (MoAb 3G8) was higher in the AIDS population than in controls, though this difference was not seen on cultured Mo. The level of FcRI expression, evaluated as mean fluorescence intensity (MFI), was higher on freshly separated Mo from AIDS patients than from controls but this difference disappeared also with differentiation of Mo to Mo-derived macrophages in vitro. Parallel analysis of FcRII and FcRIII on phagocytes revealed no differences in the MFI between the AIDS and control groups. Some observations suggested that this functional defect might be secondary to phagocyte priming by circulating IFN-gamma: (1) in vitro stimulation of Mo with hrIFN-gamma, which increased FcRI expression, actually reduced phagocytosis of IgG-coated particles; and (2) IFN-gamma concentrations were increased in AIDS patients' plasma. In spite of these findings, no significant correlation was found between plasma IFN-gamma concentrations and FcR-mediated ingestion in AIDS patients, making the hypothesis uncertain. Even if the basis for the impaired FcR-mediated phagocytosis in AIDS patients remains unclear, this functional defect may have a role in the immunopathogenesis of AIDS, constituting a component cause of the immunodeficiency.

Acquired Immunodeficiency Syndrome↗

Phonological devices in poems by English and Italian children.

Poems were elicited from 133 English children between two and six and 171 Italian children between three and seven, using a similar technique, and the results were compared. Both groups produced large numbers of poems. There were great similarities and some differences. The majority of poems in both samples contained phonological devices (mostly rhyme and alliteration) and the proportion was higher (87%) in the Italian sample than in the English sample (59%). The proportion of poems that contained rhyme was close to 45% in each sample, with no consistent age difference in either sample. About one-third of Italian poems and just over a fifth of English poems contained alliteration. The frequency of alliteration declined with age in the English sample but not in the Italian sample. Possible reasons for the differences between the samples are considered. It is argued that the similarities are more important, and their theoretical implications are discussed.

Child↗

[The parenteral administration of essential amino acids in patients on periodic hemodialysis treatment. A pilot study].

In an attempt to improve the nutritional status of seven hemodialysed patients, 500 ml of a 5.5% nephrological essential amino acid solution (EAA) were administered during each dialysis session for 2 months. At the end of this treatment, a significant increase in albuminemia was found (p < 0.05). These results are an encouragement to continue this therapy, especially if it is kept in mind that the half-life of albumin is much shorter than the period of EAA administration.

Adolescent↗

[Echo-guided percutaneous celiac plexus block with alcohol with an anterior approach].

The authors report the use of ultrasound as a guide to the execution of celiac plexus alcoholization with the anterior approach. Five patients with severe pain resistant to pharmacologic treatment with NSAID, cortisone and morphine have been treated. Once found out the celiac trunk and the best direction, using ultrasound, the needle is advanced slowly beyond the anterior lateral wall of the aorta, in order to recognize the tip with the same ultrasound response of the retroperitoneal tissue. After calculating the distance between the celiac trunk and the needle tip, this is withdrawn in order to be set in the alcoholization point of injection. No complication directly related to the technique has been observed in the five patients. Pain relief was optimal in four out of five patients and was kept until the exitus.

Celiac Plexus↗

Zinc supplementation reduces blood ammonia and increases liver ornithine transcarbamylase activity in experimental cirrhosis.

Zinc deficiency is common in cirrhosis and may be involved in the alteration of ammonia metabolism. Rats with carbon tetrachloride-induced cirrhosis have high plasma ammonia and low serum and tissue zinc levels. We used this model to examine the effects of oral zinc supplementation on activities of plasma ammonia and liver ornithine transcarbamylase (a key enzyme in the urea cycle). These parameters were examined in two consecutive experiments. Each experiment included two groups of rats treated with carbon tetrachloride; one group received zinc in the drinking water during the induction of cirrhosis, and another served as a control group. Regardless of zinc supplementation, all carbon tetrachloride-treated rats exhibited similar micronodular cirrhosis, with similar histological appearance and liver function impairment. Cirrhotic rats without zinc supplementation showed high plasma ammonia and low serum and hepatic zinc levels and reduced liver ornithine transcarbamylase activity. Serum, hepatic zinc and liver ornithine transcarbamylase activity increased significantly in the zinc-supplemented group, and these rats' plasma ammonia levels became normal. Plasma ammonia level was significantly inversely correlated with liver ornithine transcarbamylase activity and positively correlated with serum and hepatic zinc content. Our results suggest that zinc deficiency may modify hepatic ornithine transcarbamylase activity and, therefore, ammonia disposal.

Administration, Oral↗

The effect of lactulose and lactitol administration on fecal fat excretion in patients with liver cirrhosis.

Mild to moderate fat malabsorption is frequently present in patients with liver cirrhosis. We investigated the influence of lactulose or lactitol treatment on fecal fat excretion in 18 patients with liver cirrhosis. All patients were Child Pugh class A or B and had not taken any therapy that could have affected intestinal absorption in the previous months. The dose of lactulose or lactitol was individually adjusted to maintain two semiliquid bowel movements per day. Steatorrhea was determined before and after a minimum of 7 days, when the cathartic effect was stabilized. Treatment with nonabsorbable disaccharides induced mild to moderate steatorrhea in 50% of patients. No differences were observed between the effects of lactulose and lactitol, but fecal fat excretion exceeded 10 g/day in two patients taking lactulose. These findings indicate that treatment with nonabsorbable disaccharides may increase fecal fat excretion in patients with liver cirrhosis. This factor should be taken into consideration when a cirrhotic patient has to take these drugs for a long time.

Adult↗

[Indications for the use of latissimus dorsi myocutaneous flap in breast reconstruction. Personal experience].

The paper illustrates the results of the application of the latissimus dorsi myo-cutaneous flap in breast reconstruction following mastectomy due to cancer in five patients with three different indications. Following a critical evaluation of the indications and results of breast reconstruction using the rectus abdominis myocutaneous flap, the Authors conclude by confirming the validity of indications given and the positive characteristics of the myo-cutaneous flap used.

Adult↗

Basal energy production rate and substrate use in stable cirrhotic patients.

The basal energy production rate was measured using indirect calorimetry in 25 stable cirrhotic patients and 10 controls of comparable age. The endogenous substrate oxidation was also calculated by measuring urinary nitrogen excretion. The energy production rate was similar in cirrhotic patients and controls. The origins of liver disease and the degree of liver damage did not seem to influence the energy production rate. On the other hand, in cirrhotic patients, as in controls, a significant correlation was present between the energy production rate and parameters of body size, such as body weight and fat-free mass. As a consequence, cirrhotic patients with poor nutritional status, with a reduced fat-free mass, showed a lower energy production rate. The measured energy production rate was compared with the resting energy expenditure estimated by formulas commonly used in healthy individuals. The good agreement found between the measured energy production rate and calculated energy expenditure suggests that these formulas may be applied to stable cirrhotic patients in clinical practice. In cirrhotic patients, the oxidation of endogenous fat is the main contributor to basal energy production rate. The fat oxidation rate does not appear to be influenced by the hormonal pattern found in the cirrhotic patients. However, a significant correlation was present between fat oxidation and plasma free fatty acid levels. This confirms that the prevalent fat use in cirrhotic patients is supported by the greater availability of fat-derived substrates.

Blood Glucose↗

[Solar keratosis: a histochemical study on the distribution of SH groups and SS bonds].

The distribution of free SH groups and SS covalent linkages in hypertrophic, atrophic, acantholytic, bowenoid, pigmented solar keratoses (SK) and squamous cell carcinoma was evaluated. The sulphydryl groups were present in cytoplasms with a granular pattern and nucleoli mainly in atrophic, hypertrophic and bowenoid SK; the distribution of SS linkages appeared as a brilliant ovoid fluorescence localized in living layers, due to individually keratinized cells in SK. Similar results were found in squamous cell carcinoma. Our results agree with the opinion which considers SK as in situ carcinomas.

Carcinoma, Squamous Cell↗

[Propofol for the induction and maintenance of anesthesia in ophthalmic surgery].

After brief mention of the chemical and pharmacodynamic properties of diisopropylphenol, personal experience on the administration of propofol for induction and maintenance of anaesthesia for ophthalmic surgery is reported. The results have shown that induction of anaesthesia by propofol injection is associated with a significant and useful reduction of IOP more than TPS induction. Continuous infusion of Diprivan provides satisfactory conditions for intraocular surgery and could be a real choice to thiopentone combined with enflurane.

Adolescent↗

Lactitol in prevention of recurrent episodes of hepatic encephalopathy in cirrhotic patients with portal-systemic shunt.

Recurrent episodes of hepatic encephalopathy (HE) frequently occur in surgically shunted cirrhotic patients. The prevention of these episodes is based mainly on the long-term use of lactulose. Recently, lactitol, a nonabsorbable disaccharide similar to lactulose, has been proposed as an alternative in the management of HE. It has the advantage of being better tolerated and producing a more predictable catharsis. The effects of the two agents were compared in a controlled randomized study lasting six months involving 31 cirrhotic patients with portal-systemic shunt, of whom 40% experienced HE. The PSE index (mental state, EEG, asterixis, Raitan test, and ammonia) was assessed in each patient on entry to the study and every three months during treatment. Episodes of HE, side effects, and the patients' comments on efficacy, tolerability, and palatability were recorded. The dose required to induce two bowel movements per day was 48 +/- 25 ml of lactulose syrup and 36 +/- 7 g of lactitol. During the study, the number of patients who had an episode of HE and the PSE index was similar in both groups. The patients judged lactitol better from the point of view of palatability. Meteorism and flatulence, experienced by patients treated with lactulose, was not reported by the lactitol group. We concluded that lactitol is as effective as lactulose in the long-term prevention of episodes of HE in cirrhotics with portal-systemic shunt and may be better tolerated.

Adolescent↗

Renal involvement in leprosy.

Renal involvement in Hansen's disease was evaluated in 94 Portuguese patients, average age and duration of disease of 47.6 and 6.8 years respectively. Sixty-seven were studied retrospectively and 27 prospectively; renal biopsy was obtained in 4, fat-tissue needle aspiration for amyloidosis in 20, and tubular function was tested in ten. Mild proteinuria and/or haematuria was found in 33 patients, the severity increasing during erythema nodosum leprosum reactions, but without overt nephritic or nephrotic syndrome. Two patients had renal amyloidosis on biopsy and two more were confirmed by fat biopsy, a 10.5% incidence in those studied prospectively; all but one were of the lepromatous type, with frequent bouts of erythema nodosum leprosum. The two other renal biopsies showed mesangial glomerulonephritis, and one unexplained acute tubular necrosis; none had immune deposits by immunofluorescence. Proximal acidification was always normal, distal acidification tested by bicarbonate infusion was abnormal in one of nine patients, and six of nine patients had concentration defects. Leprosy causes frequent urinary sediment changes and concentration defects, usually without clinical expression; proteinuria and/or glomerular involvement is mainly due to amyloidosis.

Adolescent↗